Polyazo dyes and process of making same



Patented Dec. 14, 1926.

UNITED STATES PATENT OFFICE.

EMMET F. HITCH, OF WILMINGTON, DELAWARE, AND FRANCIS H. SMITH, OF WOODS- TOWN, NEW JERSEY, ASSIGNORS TO E. I. DU PONT DE NEMOURS 8: COMPANY, OF WILMINGTON, DELAWARE, A CORPORATION OF DELAWARE.

PoLY'Azo DYES AND rnocnssor MAKING SAME.

No Drawing. Application filed October This invention relates to polyazo dyes, and especially trisazo dyes, whose molecules comprise a middle component directly connected by azo couplings with two diphenyl nuclei 5 one of which is attached to a third azogroup.

We have discovered that new and valuable azo dyes can be prepared by combining two molecular equivalents of benzidine with one 10 molecular equivalent of H-acid, then combining to this intermediate product one molecular equivalent of an amine or phenol and converting the remaining relatively unstable inorganic diazonium group, by Suit- 15 able means, into a stable inorganic group.

To illustrate how these new dyes are prepared the following examples are given:

Ewa-mple [.Three, hundred sixty-eight pounds of benzidine are tetrazotized in the 2 usualmanner at 510 G. in 7 000 pounds of water'using 276 pounds of sodium nitrite and 900 pounds of hydrochloric acid (sp. gr. 1.18). A solution of H-acid is prepared by suspending 341 pounds of H-acid (mono- 10, 1923. Serial No. 667,619.

the presence of free H-acid. When this point is reached, a solution containing 360 pounds of soda ash is added and stirring continued at 1012 C. until there is no longer any test for free tetrazo benzidine. Two hundred thirty-nine pounds of gamma acid (Q-amino-8-naphthol-6-sulphonic acid) is suspended in 1500 pounds of Water and 40 pounds of caustic soda added. This solution is added immediately to thecombination of benzidine and H-acid. One hundred six pounds of soda ash is added and the charge is stirred until there is no longer. any test for the presence of free gamma acid. A solution of 110 pounds of sodium bisulphite in 1000 pounds of water is then added and the mixture heated to 50 C., the dye salted out with common salt, filtered, dried, and pulverized.

The process of the above example may be explained graphically by the following picture of the series of reactions which probably occur sodium salt) in 3000 pounds of Water and OH4NH1 CaH4N=NCl adding 37 pounds of caustic soda. This H- +4HCHZNBNOF +2NBOI+4H2O acid solution is added over a period of one 1 H t b .d. 1 t- I d eHgNHz C HlN-NCI mm to t e te razo enzi me so u ion an Benzidine Tetmmbemmme stirred until there 1s no longer any test for NH: or! NH, 011

C5H4N=NC1Q G5H4N=N moss s OzNa HOaS soa-m+mo1 nH4N=NCl aH4N=NCl H-acid First combination in acid solution.

H9 OH 0 mam-N01 0H4N==N v g SONE NB1COa"-',--i

H08 Hm-N01 Tetrazo-benzldine NH; Second comblnation+ Naogs 2-amino-8-naphthol-6-sulphonlc am-t NE, on

O4H N=N N-N-Cdh NBOaS S Na ulhN=N (*Nu OH |H4 N==N N H Na0;S

Unconverted diazo.

This unconverted dlazo body-i-NaHSOz-- NH: OH

CQHN-N N NCcH4 NBOIS SOENB cHtNH-NHSOzNa OH lHlN-N N H:

Final dye.

The new dye as its sodium salt is a dark o'wde'r which is soluble in water with a dark lue black coloration and in concentrated sulphuric acid with a dark greenish blue 5 coloration. On dilution with water a reddish blue precipitate is formed. Upon reduction with stannous chloride and hydrochloric acid it is split up into 4:4J-diaminodiphenyl, 1 :2 7 -triamino-8-naphth0l-3 6-disulphonic acid, and 2 7-diamino-8-naphthol- 6-sulphonic acid. rectly a blue black which on diazotization and development with meta-toluylenediarnine gives greenish black shades very fast to washing.

Example ll.Prepare the intermediate combination of two molecular equivalents of benzidine on one molecular equivalent of H-acid as described in Example I. Add to this combination a solution of 138 pounds of salicylic acid in 1000 pounds of water containing' 40 pounds of caustic soda. One hundred six pounds of soda ash is then added and the charge stirred until there is no longer any test for the presence of free salicylic acid. The charge is then made acid by adding 500 pounds of hydrochloric acid (sp. gr. 1.18) and heated to boiling. After cooling to 50 (1. the dye is salted out with common salt, filtered, dried,

verized.

' The dye formed probably has the following graphic formula;

and pul- It dyes cotton fibre di- The new dye is a dark green powder which is 'soluble in hot water to a dark green solution and in concentrated sulphuric acid to a reddish blue solution which on dilution gives a black precipitate. Upon reduction with stannous chloride and hydrochloric acid it is split up into 4 :4-diaminodiphenyl, 4-an'1ino- 4-hydroxydiphenyl, 1 2 7-triamino-8-naphthol-3 G-disulphonic acid, and l-amino-thydroxy-benzene-5-carb0xylic acid. It dyes cotton a yellowish shade of green.

Example ][[.Prepare the intermediate combination of two molecular equivalents of benzidine on one molecular equivalent of -acid as described in Example I. A solution of 341 pounds of H-acid (mono-sodium salt) in 2000 pounds of Water containing 110 pounds of soda ash is added to this combination and stirring continued until there is no longer any test for the presence of free H-acid. A solution of 110 pounds of sodium bisulphite in 1000 pounds of water is then added and the mixture heated at hydroxy-naphthalene l-sulphonic napl1thol-3zfi disulphonic acid. It dyes cotv ton and silk a greenish shade of blue.

Tolidine and dianisidine may be used in place of benzidine, or one molecular equivalent of tolidine or dianisidine may replace one of the molecular equivalents of 'benzidine, or one molecular equivalent of tolidine and one molecular equivalent of dianisidine may replace the two molecular equivalents of benzidine named in these examples.

Other compounds may be used as end com ponents instead of those named in the examples, such as for example :-resorcin, phenol, metaphenylenediamine, metatoluyle n e d i a m i n e metaphenylenediamine-sulphonic acid, metatoluylenediamine sulphonic acid, the cresols, cresidine, o-anisidine, cresotinic acid, alpha-naphthol, beta-naphthol, alpha-naphthylamine, beta-naphthylamine, 1-naphthol-4-sulphonic acid, l-naphthol-5-sulphonic acid, 2-naphthol-6-sulphonic acid, 2-naphthol-7-sulphonic acid, 2-naphthol-S-sulphonic acid, 1-naphthol-3 G-disulphonic acid, 1-naphthol-3 8-disulphonic acid, 2-naphthol-3:6-disulph0nic acid, 2-naphthol-G 8-disulplionic acid, 1: 8-dihydroxynaphthalene-3 6-disulphonic acid, 1 841iacid, 1- amino-5-naphthol-7-sulphonic acid, l-amino: 8 naphthol 4 sulphonic acid, 2 amino 5 naphthol-7-sulpl1onic acid, 2-phenyl-amino- 5 naphthol 7 sulphonic acid, 1 amino 8 naphthol-Qz l-disulphonic acid, l-amino-S- naphthol-S:G-disulphonic acid, l-amino-S- naphthol-l:G-disulphonic acid, 2-amino-8- naphthol-3: 6-disulphonic acid, 5: 5-'dilliycar )11- mide, 5 5-dihydroxy-7 7-disulpho-2 2- dinaphthylamine, 2 hydroxy 3 naphthoic acid, l-p-sulpho-phenyl5-pyrazolone-3-car-- boxylic acid, 1-p-sulpho-phenyl-3-methyl-5- pyrazolone, l-chloro-s u 1 p h o-p h e n y 1-3- 1ncthyl-5-pyrazolone, l-naphthylamine-e-sulphonic acid, 1-naphthylamine-5-sulphonic acid, l-naphthylamine-6-sulphonic acid, 1- naphthylaminc-'Z-sulphonic acid, 1-naphthylamine-S-sulphonic acid, l-phenyl-naphthylamineS-sulphonic acid, and l-p-tolylnaphthylamine-S-sulphonic acid.

The following graphic formulas are given as examples of the probable structure of some of the dyesformed according to the processes of the present invention A dye having meta-toluylene-diamine as end component:

NH! OH N=N-cun CcHc-N=N NaOaS I s OsNa 5H4-N1INH OzNB A dye having cresotinic acid as end component NH: 0H

C5H4-N=N N-.=N-C5H H038 50311 i CGHrOH H -N=N coon Ha A dye having 1: 8-dihydroxy naphthalene- 4-sulphon1c acid as end component:

.A dye having 5:5'-dihydroxy-7:7-disul pho-2:2-dinaphthyl carbamide as end com- A dye having 5 5-dihydroxy-7 7 -'disul- 'pho-2:2-dinaphthylamine as end component N=N-CQH4 on OH n 4N"N News NH/ 1 501m I soaNa cflmNnNasogm A dye having 1-p-sulpho-phenyl-3-methyl- 5-pyrazolone as end component:

A dye having l-phenyl naphthylamine-8- sulphonic acid as end component:

In Example II, above, the fourth, or'renaining, diazonium group is converted by heating with hydrochloric ac1d 1nto an hydroxyl group; while in Examples I and III,

the remaining diazonium group is probably converted by heating with SOdlllITl sulphite (the sodium bisulphite being added to an alkaline solution) to a group having the formula: NHNHSOQNa. The latter group,

as well as the hydroxyl group, are far more stable than the diazonium group.

The structure of our new dyes may be indicated by the following graphical formula:

] naphthol-3,6-disulfonic acid, coupling this intermediate product with one molecular equivalent of an end component, and convert ing the remaining diazo group into a stable inorganic group. p

2. The process of producing polyazo (1 es which comprises com'bmmg two molec a'r equivalents of a tetrazo compound contaming a diphenyl nucleus with one molecular equivalent of 1,8-aminonaphthol-3,6-disulfonic acid, coupling this intermediate product with one molecular equivalent of an aromatic compound of a class which includes amines and phenols, and converting the remaining diazo group into a stable. inorganic group.

3. A process as defined in claim 1 in which the remaining diazo group is converted into a hydrazine sulphonic acid group containing most probably the following atomic structure: NHNHSO 4. A process as defined in claim 2 in which the remaining diazo group is converted into a stable group by heating in an alkaline solution to which sodium bisulphite has been added.

5. A polyazo dye having 'most probably the following formula:

intermediate with one molecular equivalent of a phenol, and converting the remaining dlazo group into a more stable inorganic group, said dye yielding upon reduction with stannous chloride and hydrochloric acid 4,4'-diamino-diphenyl, 1,2,7tri'amino-8-naphthol-3,6-disulphonic acid, the amino derivative of said phenol, and a diphenyl com pound having an amino group in 4-position, and a stable inorganic group, other than an aniino group, in V-position.

7. A polyazo dye having most probably the following formula:

where X represents a; stable inorganic group, R and R represent diphenyl radicals, R

' stands for the divalent radical of 1,8-aminonaphthol-3,6-disulphom'c acid, and R stands for an aromatic end component.

8. A polyazo dye having most probably here X represents a stable inorganic group, a

1 and R represent radicals of compounds having diphenyl nuclei, R stands for the divalent radical of 1,8-amin0naphthol-3,6-disul holnic' acid, and Rf stands for a phenol ralea divalent radical of 1,8-aminonaphthol-3,6-di- 9. A polyazo dye having most probably sul honic acid, and R stands for a naphthol the following formula:

ra ica-l.

2 S X R R R R In testimony whereof we affix our signawhere X represents a. stable inorganic group, tures. R and R represent radicals of com ounds EMMET F. HITCH. having diphenyl nuclei, R stands or the FRANCIS H. SMITH. 

